Home care continues to be one of the fastest growing and potentially most important sectors of the health care industry in the present era of rising costs and cost containment. In addition to licensed and certified providers (LPs) of home care, there is an even larger sector of unlicensed/uncertified providers (UPs), about which little is known. Project aims are to address four sets of questions: 1) What are the organizational characteristics (structure) of UPs in three sites and how do UPs "perform" on cost, access, and quality? 2) How do UP and LP structure and performance differ? 3) What are the interrelationships among cost, access, and quality? In what ways does the structure of UPs and LPs influence performance (cost, access, and quality)? And how do environmental characteristics (policy context, regulatory intensity and SMSA market structure) influence these relationships? and 4) What are issues, incentives and barriers concerning licensure/certification? The proposed project will execute an exhaustive search to identify a census of home care UPs in 3 SMSAs: San Francisco/Oakland, CA (SFO), Philadelphia, PA (PHI), and Houston, TX (HOU). Telephone interviews will be conducted with a probability sample of 480 UPs (160/SMSA) and 120 key informants (40/state-SMSA) who are policymakers and health industry leaders. Study data will be examined descriptively (Aim 1), comparatively (Aim 2), and analytically using a predictive model (Aim 3). Comparative analytic data will be provided from a probability sample of LPs interviewed (1990) in another study. Project findings have implications for improving health care delivery and public policy.